how do carriers lock their handsets

[374802]

just curios how carriers lock their handsets so people can only use them with their network? Is the phone locked when the sim card is first put in, or do the carrier actually open up the box of the phone and add some firmware then repackage it?

[Lurick]

The firmware is installed during manufacturing in most cases and then phones are packaged up in the packaging for the various carriers and sent over to a distribution center for final shipments to the stores.

[Zmax]

There are ways to unlock and old phone. But in Canada all new phones are unlock , and can be use on any Provider

 

That is what I was told, not sure if truth

[demonix00]

It would be done during manufacture as network locked handset would normally have network specific apps pre-installed along with a network specific starting screen not to mention those handsets would most likely go down a different packaging line to be placed into packaging that would have network specific branding on it.